Add a helper function to retrieve P-SEAMLDR information, including its
version and features, using the dedicated P_SEAMLDR_INFO API. This is in
preparation for exposing this information to userspace. Userspace will
utilize the version number to verify the compatibility of TDX modules
with the P-SEAMLDR
Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
Tested-by: Farrah Chen <farrah.chen@xxxxxxxxx>
---
arch/x86/virt/vmx/tdx/seamldr.c | 28 +++++++++++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/arch/x86/virt/vmx/tdx/seamldr.c b/arch/x86/virt/vmx/tdx/seamldr.c
index a252f1ae3483..c2771323729c 100644
--- a/arch/x86/virt/vmx/tdx/seamldr.c
+++ b/arch/x86/virt/vmx/tdx/seamldr.c
@@ -11,7 +11,26 @@
#include "tdx.h"
#include "../vmx.h"
-static __maybe_unused int seamldr_call(u64 fn, struct tdx_module_args *args)
+ /* P-SEAMLDR SEAMCALL leaf function */
+#define P_SEAMLDR_INFO 0x8000000000000000
+
+struct seamldr_info {
+ u32 version;
+ u32 attributes;
+ u32 vendor_id;
+ u32 build_date;
+ u16 build_num;
+ u16 minor_version;
+ u16 major_version;
+ u16 update_version;
+ u8 reserved0[4];
+ u32 num_remaining_updates;
+ u8 reserved1[224];
+} __packed;
+
+static struct seamldr_info seamldr_info __aligned(256);
+
+static inline int seamldr_call(u64 fn, struct tdx_module_args *args)
{
u64 vmcs;
int ret;
@@ -42,3 +61,10 @@ static __maybe_unused int seamldr_call(u64 fn, struct tdx_module_args *args)
return ret;
}
+
+static __maybe_unused int get_seamldr_info(void)
+{
+ struct tdx_module_args args = { .rcx = __pa(&seamldr_info) };
+
+ return seamldr_call(P_SEAMLDR_INFO, &args);
+}
--
2.47.1
